开孔转盘塔(RPDC)连续相流体轴向混合的研究

本文采用非理想脉冲示踪技术,借助于计算机数据采集系统,在无传质条件下对RPDC连续相流体的轴向混合进行了研究。用时间域最小二乘拟合法求取了轴向混合参数,分析了RPDC连续相轴向混合的机理,得到了描述连续相流体轴向混合的数学表达式。     

DISPERSED PHASE HOLDUP AND DROP SIZE DISTRIBUTION IN A ROTATING PERFORATED DISK CONTACTOR

Hydrodynamic characteristics of rotating perforated disk contactor(RPDC)were studied with emulsionwater system.The emulsion was dispcrsed in water and its holdup was measured.The effects of columndimensions and operating conditions on holdup and characteristic velocity were studied.By using the methodof dimensional analysis,the authors obtained two experimental correlations for estimating holdup and characteristic velocity respectively.Drop size distribution was studied photographically.The experimental results showedthat drop size distribuiion could be described by upper-limit log-normal distribution.     

开孔转盘塔(RPDC)分散相滞存率及液滴直径分布的研究

本文在无传质条件下研究了RPDC内乳液-水体系的流体力学性能。测定了塔内分散相滞存率x,考察了塔几何条件及操作条件对x及特性速度u_6的影响。采用因次分析法,建立了x及u_o与塔几何条件及操作条件间的经验关联式。并采用摄影法,对分散相液滴直径d_滴及其分布进行了初步研究。实验结果表明,d_滴的分布可用上限对数正态分布来描述。     

膜技术在四川垃圾填埋场渗滤液处理中的应用

结合四川省生活垃圾渗滤液处理情况以及膜技术在渗滤液处理工程应用的实例,重点对比和分析了3家典型渗滤液处理工程工艺特点,实例证明膜技术在渗滤液处理中的应用能使渗滤液出水达到生活垃圾填埋场污染控制标准(GB 16889-2008)中相关排放标准,为我国新建或改扩建垃圾渗滤液工程工艺技术的选择提供借鉴。     

ROTATING MEMBRANE CELL TECHNIQUE FOR THE STUDY OF LIQUID/LIQUID EXTRACTION KINETICS.

ABSTRACT

The rotating membrane cell technique is described. Tim method has been tested on two types of systems: acetic acid extracted by isopropyl myristate, and Nickel and Zinc ions by di(2-ethylhexyl) pliosphoric acid (D2EHPA). The technique consists of a membrane, containing one oT the phases, that is glued on the base of a cylinder and that is rotated at. a definite speed. The main features of the technique are: simplicity of the set-up; good control of the transport in both phases; transfer occurring in a transient regime, limited by the kinetics of the chemical reactions at the beginning of the transfer process. Moreover, the technique offers the possibility of stirring only one of the two phases. An approximate mathematical solution is given for the case or an iuterfacial transfer reaction. The results for acetic acid are in accordance with such a mechanism. In contrast, the results for the metal cations cannot bo interpreted in the same way. The data may suggest the influence of a transfer of D2EHPA to the aqueous bulk. The technique seems to constitute a simple tool for the identification of purely interfacial reactions.     

多孔挡板流化床气泡行为的研究

本文在内径为(?)120mm 的多孔挡板流化床中,用光导纤维法和电容法测定了 Al(OH)_3粉、铜粉和 FCC 三种不同物料体系的气泡频率和气泡速度,对操作条件和挡板参数对气泡行为的影响作了研究和分析。结果表明,在一定的气速下,挡板的开孔率、孔径和板间距(级间高径比小于3)对气泡频率和气泡速度的影响较小;对属 B 类的 Al(OH)_3粉和铜粉物料,气速对气泡频率的影响可以忽略,而对属 A 类的 FCC 物料,气泡频率随气速的增大而增大。     

乳状液膜法分离二元氨基酸的研究

定义了乳状液膜法分离氨基酸的分离系数，并以苯丙氨酸(Phe)／天冬氧酸(Asp)作为研究对象，探讨了影响分离系数的主要因素。研究结果表明：用稳态条件下液膜体系中两种氨基酸的传质通量之比定义两种氨基酸的分离系数，能够较全面反映两种氨基酸及液膜体系所具有的特性以及影响分离系数的复杂因素，为改善分离效果提供理论指导。对于采用酸性萃取剂为载体的液膜体系来说，pH值是影响两种氨基酸分离系数的主要因素，而载体浓度对分离系数的影响程度相对较小。     

聚丙烯中空纤维支撑液膜提溴研究

以聚丙烯为膜材料、煤油为有机溶剂构成支撑液膜体系,研究了工艺条件对提溴传质过程的影响。结果表明,吸收液甲酸钠的浓度为0.1 mol/L时吸收效果较好;脱溴效率和传质系数均随原料液pH的增大而明显下降;原料液流量和吸收液流量越大,传质系数增大,脱溴率升高,在原料液体积流量达到80 L/h时,传质系数稳定在3.0×10-6m/s;原料液温度升高,溴在煤油和水中的分配系数升高,传质速度加快,脱溴率增加。     

管式膜MBR处理垃圾渗滤液过程中膜的性能研究

采用管式膜MBR工艺处理垃圾焚烧场渗滤液,考察了长时间运行下管式膜通量的变化及操作压力、循环流量、温度、污泥含量等对管式膜性能的影响.结果表明,当循环体积流量达到1 000L·h-1、操作压力0.13 MPa时,膜通量达到48.02 L·m-2·h-1,膜通量随着操作压力升高而升高;随着温度的升高膜通量呈上升趋势,当温度达到32.7℃时,平均膜通量达到107.5 L·m-2·h-1;污泥含量对膜通量影响不大,污泥质量浓度在30～45 g·L-1时,膜通量仍能维持在75～100 L-m2·h-1;通过适当的膜清洗(NaClO溶液清洗),管式膜能保持在较高的通量(≥75 L·m-2·h-1,温度27.4～32.1℃)下长时间稳定运行.     

ON THE MOMENT COEFFICIENT CALCULATION OF A ROTATING DISK IN A TURBULENT FLUID FLOW

Mixing in co-rotating sinusoidal cavity flows is studied with period, T, and phase shift, a, as parameters. Notice that the main obstacle to uniform mixing is the existence of stable :ower periodic orbits, mixing windows, where uniform mixing takes place, are found in the T— a space u:iing bifurcation analysis. The main advantage of this method is a great saving of the computation time.     

膜蒸馏法分离乙醇水溶液的研究

采用改性后的陶瓷膜管,对低浓度乙醇水溶液进行了膜蒸馏的试验研究.重点考察了膜蒸馏过程的操作参数对膜通量和分离因子的影响.试验结果表明,膜通量随着乙醇浓度、膜两侧温差和真空度的增加而增加;而分离因子则随乙醇质量分数、膜两侧温差和真空度增加而减少.     

在膜分离式酶解反应器中单基质酶受叶轮剪切失活的实验研究

研究了在膜分离式酶解反应器中单基质酶受叶轮剪切失活的现象。分别采用平板、刮刀、凹槽型式的叶轮在不同转速下进行实验,并在多级膜分离式酶解反应器中进行了验证。结果表明,不同的叶轮型式和叶轮转速对酶的剪切失活影响不同。将实验数据归纳为余存酶活与叶轮型式、叶端线速度、剪切暴露时间的曲线,应用它可估计酶在工作条件下的失活程度。     

膜气体分离机理的初步探讨

努森扩散、毛细管凝聚、表面扩散和分子筛分是炭膜对气体分离的几种主要机理．膜对气体的分离并非一种机理单独起作用．而是几种机理共同作用的结果，只是其中的一种两种机理的作用比较显著。     

MEASUREMENT OF LIQUID FILM THICKNESS ON THE SURFACE OF A PARTIALLY IMMERSED VERTICAL ROTATING DISK USING A GAMMA CAMERA

The liquid film thickness on the surface of a partially immersed vertical rotating disk was determined using a gamma camera imaging system to measure the amount and spatial distribution of a dissolved 99m-Technetium pertechneiate radionuclide tracer. The method allows simultaneous measurement of film thickness in individual regions having a projected surface area of less than 1 cm² and distributed over the entire exposed surface of the disk. Measurement accuracy is limited only by counting statistics, and for these studies was better than ±4% of the absolute film thickness.

Experiments were conducted with a 31.5 cm diameter aluminum disk rotating from 18 to 99 revolutions per minute; seven aqueous solutions of glycerol and polyvinylpyrrolidone (PVP) within the viscosity range 1 to 19.7 cp were used. The average film thickness varied between 0.045 and 0.45 mm, and was a function of solution viscosity and disk angular velocity. Local film thickness was dependent on both radial and angular position, and varied from 0.5 to 3.0 times the average thickness. This variation may be important to the characterization of mass transfer when diffusion through the film is a rate limiting step     

膜分离-电催化氧化耦合处理高含量苯酚废水的研究

采用溶胶凝胶法制备TiO2溶胶,以管式炭膜(TCM)作为基体,通过浸渍法在TCM表面涂覆TiO2催化层,炭化后得到具有催化性能的TCM;将得到的管式催化炭膜作为阳极应用于自制膜反应器,将膜分离和电催化技术耦合处理高含量苯酚废水。X射线衍射(XRD)结果表明TCM表面TiO2属于锐钛矿型,具有较高的催化活性;循环伏安法(CV)表明TCM催化电极对苯酚有明显的催化氧化作用;膜分离-电催化耦合技术相比单纯电催化对苯酚有更好的降解效果,在相同处理时间内可提高约40%的去除率,是一种可行的集成技术。并探讨了膜反应器的优化运行参数。     

溶胶凝胶法氧化铝分离膜制备工艺探讨

以异丙醇铝为主要原料，将原料子处理后，用溶胶-凝胶法制备Al2O3，膜，考察胶溶剂的种类和用量、水解温度、回流时间等制备条件对Al2O3，膜微观结构的影响。研究结果表明，选择用HCl作为胶溶剂，调节溶液pH值为2．O-3．5、水与乙醇体积量比为1：1、水解温度为80～85℃左右。通过预处理，合成时间缩短，为6～8h左右，可以制得微观结构性能比较好的Al2O3膜。     

CONTINUOUS GAS SEPARATION WITH LIQUID IMPREGNATED PARTICLES IN GAS-SOLID REACTORS

The absorption of a gas in liquid filled porous particles in gas-solid reactors was studied both theoretically and experimentally. In the theoretical study a micro mode!, describing mass transport accompanied with reaction inside the particles, was implemented in the macro balance for several asymptotic operation modes. The theoretical study showed that the gas separation can be carried out very efficiently with the liquid filled porous particles, especially for the countercurrent mode of operation. The results of the simulations for the removal of H₂S from a gas stream also containing CO₂ showed that a very selective absorption process can be obtained. For these kind of selective absorption processes the simulations showed that the residence time of the particles is a crucial parameter

In the experimental part of this contribution the absorption of CO₂ in porous y-alumina particles filled with water or 2M aqueous solutions of tertiary - or primary alkanolamines was investigated. Experiments were carried out in a gas-solid reactor where the particles were falling down in an empty tube while gas was flowing co- or countercurrently. The conversion for the particles filled with water or the aqueous primary alkanolamine was predicted satisfactorily. For the particles filled with the tertiary alkanolamines, however, the experimental conversions were much higher than theoretically predicted. This difference probably must be attributed to an underestimation of the surface adsorption of CO₂ on the γ-alumina carrier which was very important for the slowly reacting tertiary alkanolamines